Ubuntu Manpage: giftrans - transform gif from gif87 to gif89, making one color transparent

NAME

       giftrans - transform gif from gif87 to gif89, making one color transparent

SYNOPSIS

       giftrans [options] [-o filename] filename

DESCRIPTION

       giftrans  converts  any  GIF  file  into  a GIF89a.  Allows for setting the transparent or
       background color, changing colors, adding or removing comments. Also code to  analyze  GIF
       contents.

OPTIONS

       -h     Print short help on stdout.

       -t     Specify the transparent color

       -T     Index of the transparent color is the background color index

       -B     Specify the transparent color's new value

       -b     Specify the background color

       -g     Change a color in the global color table

       -c     Add a comment

       -C     Remove old comment

       -l     Only list the color table

       -L     Verbose output of GIFs contents

       -V     Verbose output while converting

       -o     Redirect stdout to a file

       -e     Redirect stderr to a file

       Colors  may  be  specified  as  index, as rgb.txt entry or in the #rrggbb form. Of course,
       beware that shells will often consider the # character to start a comment and so  you  may
       have to escape it!

EXAMPLE

       To convert the white background of a gif file to transparent, use

       giftrans -t #ffffff file.gif > transparentfile.gif

BUGS

       This  program  has  been  tested  on  a HP9000/720 with HP-UX A.08.07 In this environment,
       neither lint -u nor gcc -Wall produce any messages.  If you encounter any errors  or  need
       to make any changes to port it to another platform, please contact me.

       Known bugs:

              -B  flag  won't work if there's an Extension between the Global Color Table and the
              Image Descriptor (or Graphic Control  Extension).  If  -V  has  been  specified,  a
              Warning Message will be displayed.  Will be fixed in 2.0

              Always outputs GIF89a. Shouldn't do this if version is newer.

              -D  option may output changed data instead of original data, use with caution, best
              only with then -L option.

COPYRIGHT

       Copyright (c) 24.2.94 by Andreas Ley <ley@rz.uni-karlsruhe.de>

       Permission to use, copy, modify, and distribute this software for any purpose and  without
       fee  is  hereby  granted,  provided that the above copyright notice appears in all copies.
       This software is provided "as is" and without any express or implied warranties.

VERSION HISTORY

Version 1.12.2 - 11.4.96
Changed to GNU copyright

Version 1.12.1 - 9.2.96
Fix for multi-word color names.

Version 1.12 - 17.2.95
Incorporated dumpcomment by omerzu@quantum.de (Thomas Omerzu)
Outputs original version if newer than GIF89a.

Version 1.11.2 - 14.12.94
Incorporated OS/2 port by k.rusch@ieee.org (Klaus Johannes Rusch)
Different rgb.txt file for OS/2, setmode replaced by freopen for
OS/2 (SAA C)

Version 1.11.1 - 11.8.94
Allows for use of the -g option without the -B option.

Version 1.11 - 21.7.94
Moved Plain Text Extension to the Extensions section where it belongs
Accept Unknown Extension Labels
Incorporated MS-DOS port by enzo@hk.net (Enzo Michelangeli)
Added -o and -e options to redirect stdout and stderr
Added -D debug flag

Version 1.10.2 - 22.6.94
Support for -DRGBTXT flag

Version 1.10.1 - 21.6.94
Different rgb.txt file FreeBSD/386BSD

Version 1.10 - 19.6.94
Added option to change a color in the global color table
Added option to change the color for the transparent color index

Version 1.9.1 - 7.6.94
Different rgb.txt files for X11 and Open Windows

Version 1.9 - 1.6.94
Fixed a bug which caused color names to be rejected.

Version 1.8 - 30.5.94
Accept #rrggbb style arguments.
Do nothing if rgb-color not found in GIF.

Version 1.7 - 16.5.94
Added -l option to only list the color table.
Added -L option for verbose output without creating a gif. Added -b option to
change the background color index.
Display all matching color names for color table entries.
Fixed a bug which caused bad color names if rgb.txt starts with whitespace.
Doesn't use strdup anymore.
Fixed =& bug on dec machines.

Version 1.6 - 5.4.94
Added color names recognition.

Version 1.5 - 15.3.94
Added basic verbose output to analyze GIFs.

Version 1.4 - 8.3.94
Fixed off-by-one bug in Local Color table code.
Added option to add or remove a comment.
Transparency is no longer the default.

This man file made 9.8 from documentation in the program source code by Kai Nordlund
(knordlun@fltxa.helsinki.fi).

THANKS

       Thanx for bug reports, ideas and fixes to

              patricka@cs.kun.nl (Patrick Atoon)

              wes@msc.edu (Wes Barris)

              pmfitzge@ingr.com (Patrick M. Fitzgerald)

              hoesel@chem.rug.nl (frans van hoesel)

              boardman@jerry.sal.wisc.edu (Dan Boardman)

              krweiss@chip.ucdavis.edu (Ken Weiss)

              chuck@trantor.harris-atd.com (Chuck Musciano)

              heycke@camis.stanford.edu (Torsten Heycke)

              claw@spacsun.rice.edu (Colin Law)

              jwalker@eos.ncsu.edu (Joseph C. Walker)

              Bjorn.Borud@alkymi.unit.no (Bjorn Borud)

              Christopher.Vance@adfa.oz.au (CJS Vance)

              pederl@norway.hp.com (Peder Langlo)

              I.Rutson@bradford.ac.uk (Ian Rutson)

              Nicolas.Pioch@enst.fr (Nicolas Pioch)

              john@charles.CS.UNLV.EDU (John Kilburg)

              enzo@hk.net (Enzo Michelangeli)

              twv@hpwtwe0.cup.hp.com (Terry von Gease)

              k.rusch@ieee.org (Klaus Johannes Rusch)

              omerzu@quantum.de (Thomas Omerzu)

              Willem.Vermin@sara.nl (Willem Vermin)

              wjones@tc.fluke.COM (Warren Jones)